Heartless Summoning

Creature spells you cast cost {2} less to cast.
Creatures you control get -1/-1.

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Dimir Machinations

Look at the top three cards of target player's library. Exile any number of those cards, then put the rest back in any order.
Transmute {1}{B}{B} ({1}{B}{B}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Swamp

Grinding Station

{T}, Sacrifice an artifact: Target player mills three cards.
Whenever an artifact enters, you may untap Grinding Station.

Dark Ritual

Go for the Throat

Beseech the Queen

({2/B} can be paid with any two mana or with {B}. This card's mana value is 6.)
Search your library for a card with mana value less than or equal to the number of lands you control, reveal it, put it into your hand, then shuffle.

Profane Tutor

Suspend 2—{1}{B} (Rather than cast this card from your hand, pay {1}{B} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Search your library for a card, put that card into your hand, then shuffle.